What instrument did audiologist used to clarify your hearing loss? I mean to understand your hearing loss.

In a soundproofed booth I was given in-the-ear headphones and various frequency (250Hz to 16kHz) tones at different levels were played. Some tones warbled their frequency so that they sound different to steady tinnitus sounds. I pressed a button when I heard each tone.Then words were played and I was to verbally repeat them. Then words with background noise were played with the background noise increasing and I was to verbally repeat them.

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Yes, looks an abnormal range, my professor was considering 2-3kHz.

Old people lose hearing sensitivity to all high frequencies but most loss is from 10kHz to 20kHz. Look at the graph I posted. Since a hearing aid has difficulty producing high frequencies loud enough then a standard system is to play high frequencies one octave lower. People exposed to loud noise or gun blasts for long durations become deaf to many frequencies, 2kHz to 3khz is the most common.Telephones and AM radios do not play frequencies higher than 3khz but the important consonants sounds in English speech go to 14kHz or higher and without them then speech in not understood.

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Which feedback you are talking about?

Acoustical feedback when the mic can hear the earphone and the sound goes around and around. The gain at high frequencies of my hearing aids is 40dB (100 times) or more so the standard anti-feedback system in the hearing aids was usually used to eliminate the feedback (high frequency squealing if an earplug becomes loose or if a sound reflecting window or something is close to a hearing aid). The anti-feedback system causes high sound frequencies to flutter that makes music or the beeps from my test equipment sound bad. Some cheap anti-feedback systems simply cut all high frequencies that is a very poor way to do it.

The high sensitivity Mode has very high gain so that somebody talking far away sounds loud and clear like they are near me One directional microphone picks up a distant sound but the other mics reject and cancel background noises from other directions.

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I see, real deaf person could feel it. Let me check how much I have lost !

I did not know that I had a serious high frequency hearing loss since it occurred very slowly over the years and I did not know that all older people lose high frequency hearing sensitivity. I always protected my hearing from loud noises so I thought my hearing was still good.

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I saw the companies website you recommended, seems like they have technically sound research engineer and resources. People here in South Korea also trying to make things more tinny with energy harvesting idea.

The Chinese website Banggood has the cheapest and poorest quality "hearing aid" I have ever seen. I watched South Korea Goldstar company grow up and become LG Electronics (Lucky Goldstar) and South Korea Samsung company grow up. Maybe they made high quality hearing aids.

Then words with background noise were played with the background noise increasing and I was to verbally repeat them.

I see, these booth are available in any ENT medical center?

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Look at the graph I posted. Since a hearing aid has difficulty producing high frequencies loud enough then a standard system is to play high frequencies one octave lower.

If so, then what amplifier system you prefer? If we need boosted gain in high frequency, what should be the basic IC ? Can you suggest any company like TI,AD,Linear, ST?or, you suggest raspibary pi?

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People exposed to loud noise or gun blasts for long duration become deaf to many frequencies, 2kHz to 3khz is the most common.

Dont you think, I need a survey at my won country considering in-general deaf people?. Yes, I do believe your graph.But from your experience, it looks critical deaf person need special hearing aid.

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(high frequency squealing if an earplug becomes loose or if a sound reflecting window or something is close to a hearing aid). The anti-feedback system causes high sound frequencies to flutter that makes music or the beeps from my test equipment sound bad. Some cheap anti-feedback systems simply cut all high frequencies that is a very poor way to do it.

Let me know, which way(circuit system) you feel it poor and inadequate capabilities.

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The high sensitivity Mode has very high gain so that somebody talking far away sounds loud and clear like they are near me One directional microphone picks up a distant sound but the other mics reject and cancel background noises from other directions.

Then which point you think, need to be work in this case ? In what device you find this information?

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I watched South Korea Goldstar company grow up and become LG Electronics (Lucky Goldstar) and South Korea Samsung company grow up. Maybe they made high quality hearing aids.

Yes I heard so, I am working in this country as an Engineer but my mother land in Bangladesh. I am thinking about my poor people who need a cheaper one, I know china get priority in our market, but no trend has been build up internally who can make circuits,pcb patent along with good research activities.

The soundproof booth used for hearing tests is available at every hearing aid clinic. In my small city there are about 15 hearing aid clinics. I had free hearing tests at 3 of them.

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If so, then what amplifier system you prefer? If we need boosted gain in high frequency, what should be the basic IC ? Can you suggest any company like TI,AD,Linear, ST?or, you suggest raspibary pi?

My hearing aids are digital but they must use some analog circuits in their custom made IC. I do not know any opamp that can be powered from only 1.45V at an extremely low current like my hearing aids.

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Dont you think, I need a survey at my won country considering in-general deaf people?. Yes, I do believe your graph.But from your experience, it looks critical deaf person need special hearing aid.

Since all old people lose high frequency hearing sensitivity then they all need hearing aids programmed to eliminate their loss after a proper hearing test but many old people do not care about hearing sounds properly or cannot afford the high cost of a hearing aid.

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Let me know, which way(circuit system) you feel it poor and inadequate capabilities.

I worked with high quality telephone and video conferencing systems. They use a digital echo canceller to make a model of the acoustics (frequencies and their phases) and use it to cancel feedback sounds.Hearing aids should also do it like that.

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Then which point you think, need to be work in this case ? In what device you find this information?

Hearing aids with front, back, left and right mics can use a comparator to determine the loudest sounds at voice vowel frequencies and their direction.

The Chinese website Banggood has the cheapest and poorest quality "hearing aid" I have ever seen. I watched South Korea Goldstar company grow up and become LG Electronics (Lucky Goldstar) and South Korea Samsung company grow up. Maybe they made high quality hearing aids.

Yes, I admit as a shopper I am a "bottom feeder", and look for cheap stuff, as long as it works I am willing to put up with strange imported stuff. Hate to waste resources. I looked up lg.com, and didn't find anything in the way of hearing aids. Although they do lots of cell phones, washing machines, monitors and other stuff.

Actually I'm a licensed architect and not an electronics whiz, although I have built electronic stuff in the past, remember HeathKit? Have a special interest in what they used to call "Appropriate Technology", things that help people in village cultures in developing countries live a bit better, especially.

Its good to hear you folks (esp Hasan and Audio) sitting down and study this hearing thing, trying to figure out what people really need in the way of features and benefits, and what is possible. Its important.

Hope you celebrate a very special "Happy New Year". Lets pray for you to have a nice staring of 2017. Sorry for my late reply, I was busy on PCB design.

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I do not know any opamp that can be powered from only 1.45V at an extremely low current like my hearing aids.

Dont you mean its a build-in IC? I saw a small size SpO2 (pulse-oxymeter) from German company, its main mcu was really hidden and I found no further information other then simple SPI data reading format.

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Since all old people lose high frequency hearing sensitivity then they all need hearing aids programmed to eliminate their loss after a proper hearing test but many old people do not care about hearing sounds properly or cannot afford the high cost of a hearing aid.

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I worked with high quality telephone and video conferencing systems. They use a digital echo canceller to make a model of the acoustics (frequencies and their phases) and use it to cancel feedback sounds.Hearing aids should also do it like that.

Didnt you get any idea of "echo canceller" on circuits ? It might be in case of software resolution on signal. I dont know how unwanted signals could cancel through DSP, its obviously far away from any hardware filter. Patterns of speech, tone etc component could be meaningful if you play with them in algorithm. Most interesting thing is how the data looks like? How you captured them on program.

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Hearing aids with front, back, left and right mics can use a comparator to determine the loudest sounds at voice vowel frequencies and their direction.

Well said, even the initial design could be bulky but we can see how the loudest sound gain on particular frequencies changes on direction.

I am curious if anyone has though of using a beamforming microphone, there is one on my laptop for video conferencing in noisy environments like a coffee shop. Combine such a mic with active acoustic cancellation headphones (ear bud sized) with audio input on each ear for the hearing impaired. The headphones gets rid of all outside sounds completely while a forward aimed beamforming mic would really focus ones hearing on whoever they are looking at in front of them even in a noisy environment. Obviously for the mic, you should also be able to EQ it, but you wouldn't have to worry as much about feedback. I do realize this is a costly combination of tech.

The conference system that I worked with used a digital echo-canceller IC that required setup by playing pink noise through the speakers into the room and the mic picked it up and compared it with the original signal and made a model of the acoustics (frequencies and their phases) of the room. Then when sounds from the speakers are picked up by the microphones the echo canceller circuit cancelled them from producing acoustical feedback. It even worked with long distance that has a delay: I talk and my voice goes to the distant end where its mic picks up the speaker sound and the echo canceller at the distant end prevented my voice from coming back to me as an echo.

Since my hearing aids use 4 microphones and since the one that has the strongest sound pickup is given the most gain, then the mics must be directional. Noise cancellation is also done in my hearing aids except not in the Music Mode.

Frequently when I am in a store or in a mall I hear a song that I like playing very faintly on the background music system. I push the button on my hearing aid so that they go into the very sensitive mode then I hear the music playing loud and clear. The background noise does not increase so it must be cancelled a little and I think the very high frequencies are reduced a little.

The WOW opamp is rated to work at 0.9v. Maybe a fraction lower.With a little tuning of the circuit below for adjusting 3 frequency bands something like 3khz 6khz & 10khz, you can make a cheap but fairly functional device.

Watching with interest. Ever since I sadly washed my hearing-aids at the age of 22 (a loooooong time ago now) I've just gotten on with life without them because of the cost, thank goodness for the internet and everyone being able to communicate using text

The headphones gets rid of all outside sounds completely while a forward aimed beamforming mic would really focus ones hearing on whoever they are looking at in front of them even in a noisy environment.

Did you read any article on this? Kindly explain more.

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Obviously for the mic, you should also be able to EQ it, but you wouldn't have to worry as much about feedback.

The headphones gets rid of all outside sounds completely while a forward aimed beamforming mic would really focus ones hearing on whoever they are looking at in front of them even in a noisy environment.

Did you read any article on this? Kindly explain more.

When I was a student at high-school, I tried the headphone / directed-microphone system, using a portable FM pocket radio and a "Talking Electronics" FM Bug with a shrouded mic, it was an excellent combination for me, so yes, being able to focus on sounds is a great idea when you're talking to people.

A system I want to try build here now is something which picks up sounds from all around the house and mixes them with the audio in the room I'm in; sort of giving me far greater situational-awareness. I like to be able to hear if my cats are calling out to me / in trouble, or likewise my wife.

Watching with interest. Ever since I sadly washed my hearing-aids at the age of 22 (a loooooong time ago now) I've just gotten on with life without them because of the cost, thank goodness for the internet and everyone being able to communicate using text

A system I want to try build here now is something which picks up sounds from all around the house and mixes them with the audio in the room I'm in; sort of giving me far greater situational-awareness. I like to be able to hear if my cats are calling out to me / in trouble, or likewise my wife.

What noise level you are thinking ? What senors you are trying to use ?Cant you combined with possible earth quack signals that is important now in a risky area.

The maximum amount of high frequency boost in the simple tone controls circuit is 10dB which is good for a man no older than about 30 years old according to the normal hearing loss graph I posted. Today I am 71 years old with a normal more than 40dB of loss at 10kHz and my audio system's treble tone control does almost nothing without my hearing aids and their more than 40dB of boost.

60 years ago hearing aids produced telephone quality (300Hz to 2kHz)*. Music goes to 20kHz and speech goes to at least 14kHz and modern hearing aids play them well.The earmolds for my hearing aids have vents so that air pressure changes are allowed then they do not cause a "plugged feeling" and the vents also allow normal level low frequencies to be heard directly. but the vents cause feedback that must be eliminated.

When you make a whole house microphone system then you will have feedback unless you wear sealed headphones. Maybe the microphone system can light a bulb or ring a bell instead (and something to turn them off).

* I measured a loss of -12dB at 3kHz on a telephone line at work. I complained to Bell and they said it is fine and is better than their maximum allowed loss of -15dB. The response began dropping at 1kHz. Vowels only.

Acoustical feedback when the mic can hear the earphone and the sound goes around and around. The gain at high frequencies of my hearing aids is 40dB (100 times) or more so the standard anti-feedback system in the hearing aids was usually used to eliminate the feedback (high frequency squealing if an earplug becomes loose or if a sound reflecting window or something is close to a hearing aid). The anti-feedback system causes high sound frequencies to flutter that makes music or the beeps from my test equipment sound bad. Some cheap anti-feedback systems simply cut all high frequencies that is a very poor way to do it.

My hearing aids are Starkey Destiny 400 BTE (Behind The Ear) and implement a anti-feedback algorithm where the output is frequency shifted (up or down, don't remember which), so that each time it re-enters, it's continually shifted until nulled. It's quite effective, as one of the more embarrassing things that can happen is having your aids hanging off your ear or in your pocket while still turned on and people looking at you like WTH is going on with you? Not anymore with these. These are the first digital ones I stuck with, as I hadn't had good experiences with digital. Really prefer the old analog.

I'm 52 and have worn aids all my life, as I was born with profound hearing loss from birth, like my twin brother. My frequency loss starts at 500Hz, yes, really. And, is off the chart at 2KHz (below -110db), so no amount of amplification is going to help there.We always wear BTE, as they are the only types that usually have the power needed with the large enough battery to last.

Funny story: Hearing loss got me started in electronics and sound. I started tinkering with amplifiers as a kid and entered a regional Science Fair at age 13 and won first place in Physics with a telephone amplifier I hacked together from a radio and a magnetic pickup coil. I still had a lot to learn, as I used a linear pot for the volume control and demonstrated that there was still plenty of volume when turned all the way down. LOL.

I'm a digital guy through and through, however, building digital circuits and programming MCUs and such.

Anyhow, I'm enjoying this thread and applaud any efforts in this field. As much as I enjoy technology and having the latest of the greatest, my experience with aids has exposed many problems in this field. The aids offer so many features and options that my main aid seller, as well as several other "professionals" that offered to fine tune these aids and fix my issues, were baffled for hours trying to figure out what to do and what to change on the software connected to the aids. This took many visits and I was left giving up on having some issues ever resolved.

One of the issues was the hearing aid confusing music as noise and always tuning it out. This was a problem I had many years prior when I was testing out a digital aid. I worked in a printing plant and needed to hear the equipment running, including pressurized air or vacuum, and drive motors. Having the aids constantly trying to tune out the sounds was extremely annoying, so I returned them. I needed to hear the noise! This was finally fixed, however, by finding a way to turn it OFF. Probably a disappointment to the team of DSP programmers who spend weeks/months making this "work."

The other issue was just simply having the telephone pickup work. This was supposed to work automatically or you could switch it manually. But, no. Unlike any hearing aid in the past, I cannot use these on any hearing-aid compatible phone. What's the point offering all these bells and whistles if no one knows how to make it all work? Inexcusable for a $3000/aid system.

Now, I like the idea of BT enabled aids and other features, but when it really comes down to it, all we really need is a good, low-power, sensitive mic, amplifier, and transducer, coupled with a 2 or 3-band filter. Everything else is gravy.

I tried frequency shifting to eliminate feedback in a PA system but it added strange sounds.The echo canceller in conference systems also made weird sounds when the acoustics in the room changed due to many people coming or going and it got confused since its model of the acoustics is different.

These are the first digital ones I stuck with, as I hadn't had good experiences with digital. Really prefer the old analog.

Let me know your digital design more.

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We always wear BTE, as they are the only types that usually have the power needed with the large enough battery to last.

For real application, what did you feel for size of battery.?

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Funny story: Hearing loss got me started in electronics and sound. I started tinkering with amplifiers as a kid and entered a regional Science Fair at age 13 and won first place in Physics with a telephone amplifier I hacked together from a radio and a magnetic pickup coil. I still had a lot to learn, as I used a linear pot for the volume control and demonstrated that there was still plenty of volume when turned all the way down

. Dont you think, its more about Physics rather then engineering work!

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I'm a digital guy through and through, however, building digital circuits and programming MCUs and such.

What MCUs you have programmed, did those related with PA,Hearing aid or telephone system?

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Anyhow, I'm enjoying this thread and applaud any efforts in this field. As much as I enjoy technology and having the latest of the greatest, my experience with aids has exposed many problems in this field. The aids offer so many features and options that my main aid seller, as well as several other "professionals" that offered to fine tune these aids and fix my issues, were baffled for hours trying to figure out what to do and what to change on the software connected to the aids. This took many visits and I was left giving up on having some issues ever resolved.Well, keep stay with us. For the case of software and firmware ,things might not easy if you apply a centered MCU with circuits. Its a challenge indeed.From this post response, people directed me in right way! Even we want to think in different angle.

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One of the issues was the hearing aid confusing music as noise and always tuning it out. This was a problem I had many years prior when I was testing out a digital aid. I worked in a printing plant and needed to hear the equipment running, including pressurized air or vacuum, and drive motors. Having the aids constantly trying to tune out the sounds was extremely annoying, so I returned them. I needed to hear the noise! This was finally fixed, however, by finding a way to turn it OFF. Probably a disappointment to the team of DSP programmers who spend weeks/months making this "work."

Right you are ! annoying work kills your brain.

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Now, I like the idea of BT enabled aids and other features, but when it really comes down to it, all we really need is a good, low-power, sensitive mic, amplifier, and transducer, coupled with a 2 or 3-band filter. Everything else is gravy.

When you make a whole house microphone system then you will have feedback unless you wear sealed headphones. Maybe the microphone system can light a bulb or ring a bell instead (and something to turn them off).

When you were talking about "feedback" microphone system, I feel need to work on that on my design.

The echo canceller in conference systems also made weird sounds when the acoustics in the room changed due to many people coming or going and it got confused since its model of the acoustics is different.

For the case of acoustics and echo canceller, cant we use a simulation software ?Can you remember from your stock ?